Engine dies while driving

While I'm driving, sometimes the check engine light will come on and then the engine will begin to miss and when I step on the gas nothing happens, or maybe I'll get a little response from the engine, but not through the whole push, and then it will die. Sometimes if I put it in neutral when this begins to happen and stomp on the gas repeatedly it will not die, but not always. When you first start the engine after it has sat for several hours there is a lot of white smoke that comes out and it smells strongly of gas. it's not leaking water